Low correlation between genes and the chances for survive indicate no or slow evolution according to genetic algorithms?

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Discussion by: Mirror

Richard has said in his book that the genes which have a phenotype that improve chances of survival will also become more common in the species.

Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?

An example would be a group of monkeys typing randomly on type writers. Given enough time they will type a shakspher play.

With uniform randomness it will take them more than the time the universe is expected to exist to type a shakspher play this way.

With a genetic algorithm the time to write a shakspher play can be reduced to something more practical.

This is also why evolution works, but also why evolution doesn't work when there is no correlation or uniform randomness.

Before you comment that there is no randomness in evolution there is randomness in everything. Randomness is a mathematical tool and randomness is not either 100% or 0%. There are all types of randomness.

And lastely, do you think evolution still happen in the human race or due to uniform randomness we evolve so slow it will take more than the time the universe will exist to introduce new different combinations of genes?

37 COMMENTS

  1. Your ‘monkeys on typewriters’ hypothesis is one of the more bizarre and ill-conceived I’ve come across.

    If you are referring to our own species (assuming I’m not conversing with one of your monkeys you left logged in to RDFRS) there are reasons to believe evolution by natural selection has been anthropomorphically changed, in (and by) humans, yes. The existence of the science of medicine means there are cures to diseases of genetic predisposition. Diseases which, in the absence of science would kill people needlessly.

    Your ‘uniform randomness’ idea reeks of lack of reading. If this were live Q&A after a scholarly debate, I dare say they’d have grappled the microphone from you, halfway through your comment. And I apologise for being the one to do so, in kind, just now.

    Edit: Honestly.. It’s “Shakespeare”, and every sentence you fumbled around his name insulted my being.

  2. Your perception of what is random and what is not random is dependent on your understanding physics along with cause and effect. Think of it like your old mathematics quizzes where you were presented with a series of numbers where you needed to recognize the pattern in order to correctly provide the next number in the series – if you don’t understand the pattern, you will have difficulty understanding the correct answer.
    In this case, you fail to understand or recognize the correlation between the events that have created the universe we exist in. If your expectation is that if evolution is real then we should be able to see new species of animals result from evolution every few years, then you will be sadly disappointed. That is not how evolution works. I don’t think that there is anybody within the scientific community that would try to convince you that evolution is a process that creates dramatic generational differences within most organisms. The common understanding between educated people is that evolution is a process that takes multiple generations within a species before a new genetic trait becomes homogeneous within that species. The speed at which evolution occurs within a species depends upon several factors such as reproductive rate, reproduction within colonies and genetic family, and the proximity to other colonies of the same species for inter-breeding.
    Not all genetic traits are beneficial to a species, and often can impede the survival of individuals within the group and their ability to reproduce (pass their genetic code to the next generation). Some genetic traits increase an individual’s ability to survive or reproduce, and thus their genetic traits will be shared with the subsequent generations of that species. This process of passing on or elimination of genetic traits is what causes our children to develop similar physical characteristics to their parents. This process is also defined as evolution.
    I would accept the idea that evolution is a random process or doesn’t occur if you can prove to the rest of the world that there is no similarity between the genetic make-up of children compared to that of their parents.

  3. You have to be careful with randomness in the natural world. Everything has some form of influence upon others, it’s not uncorrelated. As soon as you rise above Brownian motion levels anyway. It’s not ‘white noise’ anymore.

  4. It’s difficult to understand what you’re trying to express, but I’ll take a stab at it.

    First, I would say that it’s important to note that, if I understand you properly, you’re talking about a purely hypothetical, intellectual discussion. You’re talking about the logical extremity ad absurdum principle. The thought that all phenotypes have no impact on survival is purely a philosophical discussion.

    Second, on a more limited scale, what you are saying has been known since at least Darwin, before “phenotypes” was even a concept. Darwin stated that features which neither increase nor decrease a life form’s chances of survival can mutate freely – natural selection has no power to act on them. This position has been qualified so that small populations can experience “genetic drift”, whereby a feature that doesn’t impact survival can become dominant for simple statistical reasons. I suspect that, in the hypothetical (and unreal) situation of everything being random, evolution would still occur, but purely through genetic drift. Perhaps a statistician here can comment on that.

    As for humans, I’ve never understood why people think that evolution might have somehow stopped for us. It sounds to me a lot like “we are the pinnacle of evolution” ideas. Evolution is a process. So of course it is still acting on us. What has changed is that there are a many more features today that do not impact our ability to survive and reproduce, so there are many more features that can freely mutate.

  5. “And lastely, do you think evolution still happen in the human race or due to uniform randomness we evolve so slow it will take more than the time the universe will exist to introduce new different combinations of genes?”

    We have become so evolved that our very culture , social context and medical advancement is slowing down evolution of our species. Cultural Norms , biases etc will dictate in a tangible way who will and won’t mate. Also medical advancement will effect the rate of natural selection.

    On the first part ,

    Not sure I fully understand this ,

    Selection can occur in a gene pool , where traits are passed on that have no obvious advantage either in terms of their survivability or reproductive success. Not sure how that squares with evolutionary theory but if I’m wrong , I’m sure I’ll be told.

    This could explain the transitionary states , ( the irreducibility argument , etc ) , There’s probably a tipping point when suddenly the culmination of these ‘unselected’ traits ( that are driven purely by biological inheritance and mutation ) become useful and are then naturally selected for.

    • In reply to #5 by Pauly01:

      We have become so evolved that our very culture , social context and medical advancement is slowing down evolution of our species. Cultural Norms , biases etc will dictate in a tangible way who will and won’t mate. Also medical advancement will effect the rate of natural selection.

      From a gene’s eye view culture, medicine and other technology all just look like part of the environment. Fire gave us a tolerance to moderate amounts of smoke inhalation, tobacco is probably increasing the pressure in this direction. I wouldn’t be surprised if motor cars are improving our reflexes. IQ is increasing! Far too slowly for my liking, but still incredibly quickly in objective terms. Even genetic engineering, though difficult to describe as natural, is a form of selection and will likely be the next and most important step in our evolution

      • “Fire gave us a tolerance to moderate amounts of smoke inhalation, tobacco is probably increasing the pressure in this direction. I wouldn’t be surprised if motor cars are improving our reflexes. IQ is increasing!”

        Interesting

        Tobacco as a selection pressure , I doubt it. We are only smoking a very short time in the big scheme of things. It’s really presupposed on tobacco killing off people before they can start reproducing. It may increase our immunity a tad but I can’t see it having a massive impact. Unless young kids start smoking , you’d have a point then.

        IQ in large part is meme driven. Our education , learning techniques , focus on personal development and imagination are pushing the boundaries. Put now I concede since we have this barometer IQ will probably increase.

        If we ignore the hypothesis of intelligent people leaving more offspring , I am not sure if the biological drift is presupposed towards more intelligence. If it was the law of the jungle , it would be different.

        It also depends on social class , poorer classes can have many children , and IQ as a predictor for reproduction success is not guaranteed.

        Your points on genetic engineering are very relevant.

        In reply to #9 by Peter Grant:

        In reply to #5 by Pauly01:

        We have become so evolved that our very culture , social context and medical advancement is slowing down evolution of our species. Cultural Norms , biases etc will dictate in a tangible way who will and won’t mate. Also medical advancement will effect the rate of natural…

        • In reply to #12 by Pauly01:

          Tobacco as a selection pressure , I doubt it. We are only smoking a very short time in the big scheme of things. It’s really presupposed on tobacco killing off people before they can start reproducing. It may increase our immunity a tad but I can’t see it having a massive impact.

          In any case the pressure is decreasing fairly rapidly as anti-smoking laws are implemented around the globe.

        • In reply to #12 by Pauly01:

          Unless young kids start smoking , you’d have a point then.

          Street kids are always bugging me for smokes.

          IQ in large part is meme driven.

          Yes, probably in part. Memes should exert pressure on genes the same way the environment and other genes do, but I was going more for for the “intelligence is sexy” hypothesis.

        • In reply to #12 by Pauly01:

          Tobacco as a selection pressure , I doubt it. We are only smoking a very short time in the big scheme of things. It’s really presupposed on tobacco killing off people before they can start reproducing.

          Just as a nit pick, it could be a selection pressure not only if it prevents reproduction, but also if it reduces overall reproduction compared to non-smokers. But since tobacco induced cancer tends to appear after an individual’s reproductive years, you’re still probably right that it isn’t much of a selection pressure.

          It also depends on social class , poorer classes can have many children , and IQ as a predictor for reproduction success is not guaranteed.”

          As an interesting related note; if you think about standard population growth observations, economic success is actually an evolutionary negative selection pressure. :-) Why? It’s a well established fact that, particularly in the middle class, the establishment of family is delayed, and they have fewer children overall. This is why global economic growth is always touted as the best way to control world population. But it’s also selecting against the very people who are achieving social, health, and resource accumulation success in their own lifetimes.

          • In reply to #15 by downshifter:

            But since tobacco induced cancer tends to appear after an individual’s reproductive years, you’re still probably right that it isn’t much of a selection pressure.

            It may help kill off the wheezing asthmatics, plus you’re forgetting about the advantage in having grandparents.

  6. Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?

    Wow, no! The phenotype is the thing that does the surviving.

  7. Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?

    I have no idea what this means. The mods keep saying that they have a big back log of discussion topics. If this is one of the best of the group my sympathy goes to them for having to wade through so much barely coherent prose.

    • Red Dog,
      I’m in the back log. Please mods publish my discussion.
      Its about a cow, but their is a genuine scientific question in it. I will run the gauntlet if the time comes!

      In reply to #7 by Red Dog:

      Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?

      I have no idea what this means. The mods keep saying that they have a big back log of discussion topics. If…

  8. Oh dear, mis-spellings aside this looks like another, ‘evolution cannot occur because my mis-applied/selectively applied ideas of maths and probability say it cannot happen (i.e. reconfirming my preconceived ideas that I am not inclined to seriously challenge because they make me comfortable) within such and such a time frame”. Firstly, mutation may be pretty random but natural selection is not and secondly, at some point you need to get out of your head and actually investigate to determine whether evolution has actually occurred i.e. by investigating the fossil record and other indicators, rather than confining ones self to thought experiments. As the saying goes, many a beautiful philosophy has been destroyed by an ugly fact, problem is, many theists especially prefer the beautiful philosophy and seldom test their ideas lest they be blown apart by said ugly fact.

    • In reply to #10 by Typhon:

      Oh dear, mis-spellings aside this looks like another, ‘evolution cannot occur because my mis-applied/selectively applied ideas of maths and probability say it cannot happen…

      I think you’ve hit the nail on the head. This is yet another creationist post, arguing (as far as I can make out) that evolution cannot be the true answer since it’s all random. It’s a very common creationist argument.

      Notice right at the beginning that “Richard has said in his book…” Well, which one of many? Obviously not The Blind Watchmaker, since he disposes of the ‘it’s all random’ argument by reference to a single phrase of Shakespeare.

      If the OP genuinely wants to understand, genetic mutations occur mainly randomly. They are mostly neutral (that is, they have no effect) or negative (in which case the organism usually dies – but not always). Very occasionally the mutation proves to be useful within the environment the organism lives in, in which case natural selection kicks in. Natural selection is anything but random and in effect preserves the mutation so that it becomes, over many, many generations, ‘normal’ to that organism.

      As to whether we’re still evolving – yes, but many of the evolutionary pressures that might have been around when we were hunter-gatherers are mitigated by things we do to improve our lives (you might well call it ‘science’) so that natural selection doesn’t often get very far. However, for instance, we continually need to update medicines because bacteria do evolve very rapidly through natural selection (they have very short generation-spans) and things such as MRSA arise quite often.

      I really hope the OP is genuinely interested.

  9. I usually love to explain and enthusiastically go through the paces of the ideas that are being contended. I just love evolution as a topic and teach it every day.

    I also have jumped on people in the past for their grammar and spelling (not that mine is great but DAMN)…. only to find that English is their second language and I am the one being an asshole.

    Having said both of these things, I am not going to jump in with my usual modus operandi; but rather i am lurking here to see what the person who started this OP is really up to. I smell shit and do not feel like stepping in it.

  10. I think of IQ as being “the size of your coffee mug”. Not what your coffee mug is full of. I think that is why it is most accurately measured in young kids. I am scratching my head over the “we are evolving towards higher IQ’s” type of thought because I am not convinced that :

    1. It has been measured consistently
    2. It has been measured accurately
    3. It has been measured for nearly long enough to even say a movement in IQ is even a “trend”

    Having said this, I have taught kids with IQ’s over 150 who have nothing as far as a knowledge base is concerned. They have been told their whole lives how smart they are and know zero about zero. Like, never been to a zoo, no fundamental background knowledge on anything… It can be due to neglect, socio-economics, laziness, etc…

    Give me a classroom full of kids with really full average sized “coffee mugs” any day!!!

    • In reply to #18 by crookedshoes:

      Having said this, I have taught kids with IQ’s over 150 who have nothing as far as a knowledge base is concerned. They have been told their whole lives how smart they are and know zero about zero.

      Well I hope you managed to rectify this! There is nothing worse than wasted potential.

  11. This is also why evolution works, but also why evolution doesn’t work when there is no correlation or uniform randomness.

    What on Earth is “uniform randomness”? Earth is a very active planet affected by numerous cycles!!

  12. Like others I find the OP hard to follow.

    If it is being suggested that some aspects of phenotypes may be less subject to selection pressure than others, I could see that. I still have my appendix and although I guess in the end deaths from appendicitis may select out the redundant appendix genes, the selection pressure would be far less than for molecular shape changing mutations in key enzymes (which are often fatal early in life).

    The last paragraph, about ‘uniform randomness’ is perhaps the one I understand (or agree with) the least, but if I take it to assert human evolution is immensely slow there is evidence to the contrary – e.g. the rise of lactose tolerance into adulthood in northern temperate peoples, perhaps in the last ten thousand years, after the domestication of cattle – a timescale which is very short in evolutionary let alone cosmological terms (see http://en.wikipedia.org/wiki/Lactase_persistence).

    Finally, new combinations of genes arise with each conception, that is the essence of sexual reproduction. Many conceptions do not lead to viable babies on account of pre- or post-natal selection pressures upon new genes that are fatal mutations. Natural selection starts in the first hour after conception and onwards, in every human.

    In summary, deselection pressures upon fatal new genes are very strong and common, but tend to conserve phenotypes. However, as lactase persistence shows, less drastic phenotypic differences, such as adults being able to exploit the nutritional advantages of milk, can act quite quickly to favour the new genotype across whole continents.

  13. I’m not an evolutionist or a physicist, but would I be wrong if I said this OP appears at first glance to be written by someone who knows their stuff, but on second to be meaningless babble? I also thought discussion submissions were edited. When I first read it I thought ‘shakspher’ must be a scientific term that I hadn’t heard of.

  14. Maybe I am opaque, but I can see plenty of evidence that we do evolve, in the sense that our species changes, and it does it rather fast. Over the last 100000 years (let’s say, roughly 10000 generations, a number containing very few trailing zeros), we changed skin color, eyes color, hair color, height, lactose tolerance (that one happened over the last 1000 generations only). Note that I am not including any cultural adaption, only physical changes, all probably caused by the climate.

  15. “Natural selection”. It’s often the part that is omitted to push the ‘randomness’ / ‘improbable’ canard. For evolution to work, there has to be selective pressures where beneficial traits are statistically favoured, either artificially or naturally. When genetic algorithms are used, they are not used in a vacuum. Random mutations are just things that makes evolution possible, it is not ‘the thing’.

    …What the hell is a shakspher?

  16. I think your question is this. What happens when a mutation neither helps nor hurts? There is nothing to push it to become more prevalent. It will remain an oddity.

    If that gene tended to be paired with some other gene, that did affect fitness, its fate would be depend on the fitness of that other gene.

  17. The rate at which a population adapts correlates positively with how big are the fitness differences between phenotypes. Go look up selection coefficients in a book on population genetics such as Futuyma’s Evolution. Empirical selection coefficients are large enough for the rates of evolution that scientists observe or predict.

  18. Like most people who have commented on this post, I”m not sure exactly what’s going on. The genetic algorithm that is being referred to is a program that was first written by Richard Dawkins and described in The Blind Watchmaker. Briefly, the probability of choosing letters randomly and typing the sentence “Methinks it is like a weasel” (from shakspher’s Hamlet – sorry, couldn’t help it) is extremely low, but if variants of randomly typed sentences that resembled the above sentence more than rival sentences were selected using a genetic algorithm resembling the process of natural selection (although natural selection doesn’t have an end goal in sight, of course), then the sentence is arrived at, letter for letter, in a surprisingly short number of generations (the number doesn’t come to mind). This is an interesting and enlightening example of the power of natural selection when compared to random events.

    Now, the post seems to be suggesting that if it can be shown that no phenotype correlates with survival and/or reproduction then evolution cannot have taken place because it would have taken too long. There are certainly phenotypes today (even sticking with the human population) that correlate significantly with survival and/or reproduction. I wont go into any here, but with a little effort put into searching pubmed (for online scientific publications) or other relevant websites, several interesting papers on the subject can be found. However, and as other comments also highlight, modern medicine and other cultural factors have decreased or removed many of the selection pressures that affected our ancestors.

    I would like to make a few comments on correlation and randomness as mentioned in the post. First of all, nobody that knows anything about evolution would claim that there is “no randomness in evolution”. Mutation is random in the sense that mutational events usually can’t be predicted and they appear to follow no particular order (although they can of course, especially when the rate of mutation is considered). Randomness itself isn’t a mathematical tool – the simulation of random models is, usually accompanied by their comparison with non-random models (look no further than the Weasel simulation in The Blind Watchmaker I mentioned earlier). We can get philosophical about randomness and its definitions, but if it is taken to mean the absence of predictability and order (which it often is) then randomness can be precisely defined as 0% or 100% (or any percent in between) depending on the system, example, model, etc. that you are studying. A simple example: the numbers 1 to 9 are correlated perfectly with the numbers 1 to 9 so randomness is completely absent from a linear model of these two lists of numbers drawn on an x-y coordinate plot. Randomness can find its way into a model where correlation is less than 100% and can often be precisely measured as the lack of predictability of the model or the percentage of unexplained variation in the variable that one was trying to predict.

    I don’t think this post had honest intentions behind it or, in the case of the person who posted it, a willingness to understand and this quite probably explains the lack of coherence and logic running throughout coupled with the pseudo-scientific flavour to it.

  19. “Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?”

    I forgot about this one: It cannot be concluded from a lack of correlation between all phenotypes (if the collection of data for all phenotypes was possible) and chances of survival that evolution does not occur (and certainly that it did not occur). What can be suggested, however, is that (based on the data that has been analysed) there are low (or no) selection pressures acting on the population involved in the study. I’m open to disagreement of course – I’m just trying to pull some sense out of the questions/suggestions in the post.

    • In reply to #30 by vodkaholic:

      What can be suggested, however, is that (based on the data that has been analysed) there are low (or no) selection pressures acting on the population involved in the study.

      A group of clones not subject to mutation might be one entirely hypothetical example, but as soon as you get any variation…

  20. Mutation is random, evolution is not. The gatekeeper known as death filters out the “bad” mutations.

    Humans still evolve. The pressures on which direction we evolve may come from our own manipulation of our environment as much as from nature. Science is near the point where we will directly change ourselves which isn’t natural selection, but will certainly change the human species.

    Yes, things that have no direct bearing on the survival of your offspring have little influence on your evolution.

    • In reply to #32 by canadian_right:

      Science is near the point where we will directly change ourselves which isn’t natural selection, but will certainly change the human species.

      It may not yet form part of our current understanding of natural selection, but I think alien geneticists might one day be able to incorporate it into the theory as a form of sexual selection.

  21. Richard has said in his book

    which book. He’s written a few.

    that the genes which have a phenotype that improve chances of survival will also become more common in the species.

    “also” as well as what?

    Can I conclude that if there is low correlation between the phenotypes and the chances of survival then there is a uniform randomness in the chances of survival and thus no or low evolution?

    yes. But why would this happen? So-called “living fossils” might be an example (though even they evolve)

    An example would be a group of monkeys typing randomly on type writers. Given enough time they will type a shakspher play.

    do the maths. Even if you measure it in multiples of the age of the universe the time taken is vast. Or if you can’t do the maths try wikipedia.

    With uniform randomness it will take them more than the time the universe is expected to exist to type a shakspher play this way.

    much too small a number!

    With a genetic algorithm the time to write a shakspher play can be reduced to something more practical.

    This is also why evolution works, but also why evolution doesn’t work when there is no correlation or uniform randomness.

    when does this happen? Give examples.

    Before you comment that there is no randomness in evolution there is randomness in everything. Randomness is a mathematical tool and randomness is not either 100% or 0%. There are all types of randomness.

    mutations are random. But much more important is selection

    And lastely, do you think evolution still happen in the human race

    yes.

    or due to uniform randomness we evolve so slow it will take more than the time the universe will exist to introduce new different combinations of genes?

    no. Mutation is still occurring.

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